A K3 Rule is a service that reads data as it transits the system.    If the data meets a condition (WHEN) criteria expressed in a rule, then it executes the first condition response for matching records (THEN) and the second condition response for non-matching records (ELSE).   

K3 includes several rule action types. For example, a simple rule action type is "SetValue".  For example, a rule can state WHEN Zip Code equals 10016 THEN SetValue City to "New York" ELSE SetValue City to "Not New York".   Rules allow users to create rich data sets quickly and easily.

1. Navigate to the Rules screen.
2. On the lower right of the screen find the PLUS floating action button.
3. Add a descriptive name for your rule.
4. Navigate to the "When Statement"   Use type ahead inside the column search to find the data you would like to set as your when criteria.  
5. Navigate to the right to select a predicate.  For example when launch_angle uses the predicate of => or greater than or equal to.
6. Navigate to the right of the predicate and type in the criteria.  In this case we have selected => 13.
7. Continue setting When criteria as necessary.
8. User has the ability to select from 5 different rules types. These are covered in the articles that follow. Those choices are: Formal, Set Value, Copy Value, Swap Value, and Drop.